Nikki Freeman

Preprint · July 29, 2026 Digital twins for health may be used to compare treatments, project patient trajectories, and support clinical decisions. While related to mechanical digital twins, those initially developed for engineering applications, replicating the mechanical digital ... Link to item Cite

A Review of Methods and Practices for Missing Data in Sequential Multiple Assignment Randomized Trials (SMARTs): An Ancillary Study of a Scoping Review

Preprint · April 26, 2026 Background: Missing data poses an acute threat to sequential multiple assignment randomized trial (SMART) analyses because of the sequential treatment structure and response-dependent re-randomization. Objectives: This study aimed to (1) review the curre ... Link to item Cite

Statistical Design and Rationale of the Biomarkers for Evaluating Spine Treatments (BEST) Trial

Preprint · March 24, 2025 Chronic low back pain (cLBP) is a prevalent condition with profound impacts on functioning and quality of life. While multiple evidence-based treatments exist, they all have modest average treatment effects$\unicode{x2013}$potentially due to individual var ... Link to item Cite

Optimal individualized treatment regimes for survival data with competing risks

Preprint · November 12, 2024 Precision medicine leverages patient heterogeneity to estimate individualized treatment regimens, formalized, data-driven approaches designed to match patients with optimal treatments. In the presence of competing events, where multiple causes of failure c ... Link to item Cite

Bayesian Outcome Weighted Learning

Preprint · June 17, 2024 One of the primary goals of statistical precision medicine is to learn optimal individualized treatment rules (ITRs). The classification-based, or machine learning-based, approach to estimating optimal ITRs was first introduced in outcome-weighted learning ... Link to item Cite

Dynamic treatment regime characterization via value function surrogate with an application to partial compliance

Preprint · December 1, 2022 Precision medicine is a promising framework for generating evidence to improve health and health care. Yet, a gap persists between the ever-growing number of statistical precision medicine strategies for evidence generation and implementation in real world ... Link to item Cite

Stable phase retrieval for infinite dimensional subspaces of $L_2(\mathbb{R})$

Preprint · March 7, 2022 Phase retrieval is known to always be unstable when using a frame or continuous frame for an infinite dimensional Hilbert space. We consider a generalization of phase retrieval to the setting of subspaces of $L_2$ which coincides with using a continuous fr ... Link to item Cite